Workpiece treating arrangement

ABSTRACT

In a workpiece treating arrangement, a drum has an elongated member extending through the upper portion thereof for supporting a throwing wheel within the interior of the drum for treating workpieces during rotation of the drum.

[111 3,821,866 [451 July 2,1974

United States Patent [191 Carpenter 11/1928 Rich....... 7/1930 Clark... 12/1940 Webster,

ll/l96l Bigelow. 5/1964 Williams Harper...

1 1 WORKPIECE TREATING ARRANGEMENT [75 I Inventor: James H. Carpenter, Hagerstown,

[73] Assignee: The Carborundum Company,

Niagara Falls, NY.

Sept. 22, 1972 6/1971 9/1971 Reed......

[22] Filed:

Primary Examiner-Donald G. Attorney, Agent,

Kelly or F irm-The Carborundum a t a D n 0 a .m 1 p 0.. A ,5 l w e m R m D. A m

ABSTRACT nnn omm S uh a h d pls m ww w m dewP a mgm no hi m w w o mmmm ht gt mm m u ring rl r .10 ntf e n Wm m e Pm e ud s u U er. fhd emot C f .wmf u L Or. b n 60$ d i m fln w m am n w .m 0 et .mefimm 345 Hw l 4 3% N23 181. 6 9 N B i dm Mm A H 01 mm S mmm E m M mmm 8A FT. s u. :l .nh e NC R NM E m m& H d w 1 IM k UhF H N N 555 5 .l:|.[

1,343,350 6/1920 Coburn.,.................................51/13 3 Claims, 8 Drawing Figures PATENTEDJUL 21914 SHEET 1 BF 4 PATENTED JUL 21914 SHEET 3 OF 4 WORKPIECE TREATING ARRANGEMENT CROSS REFERENCE TO RELATED APPLICATION This application is a continuation-in-part of copending application Ser. No. 55,699 filed July 17, 1970, now U.S. Pat. No. 3,693,296.

BACKGROUND OF THE INVENTION Conventional universal type blast cleaning machines are suitable for high volume cleaning of small to medium size castings wherein the machines are of the continuous flow barrel type. These machines can handle large tonnages of the same parts or miscellaneous parts and handle them automatically. A particularly effective machine is disclosed in U.S. Pat. No. 3,585 ,758 which includes a spiral infeed tube and a spiral exit tube with the intermediate blast section being of the conventional slat conveyor construction. The machine disclosed in this patent includes such refinements and improvements that it is capable of handling a large variety of castings. More particularly this machine has solved the problem of breakage and thrust inherent in previous designs. Despite the effectiveness of the machine a serious problem still exists. In this respect the slat conveyor, while working satisfactorily, is a constant maintenance problem. Also, the design is a complex system of individual slats, chains, sprockets, bearings, etc., all requiring extensive engineering and creating manufacturing and maintenance problems. In addition, another problem of increasing importance is noise level. The present noise level being approximately 100 decibels on the C" scale. Federal legislation is presently being considered which will require industrial noise levels to be 90 decibels on the A scale. Noise pollutes the air the same as particulate matter and legislation will presently require lower noise levels.

SUMMARY OF THE INVENTION An object of this invention is to provide a workpiece treating arrangement which is particularly designed to overcome the above problems.

In accordance with this invention in place of the conventional slat construction, the blasting section is a slatless drum and centrifugal throwing wheels of the type disclosed in U.S. .Pat. No. 3,521,406 are disposed within the drum for treating workpieces therein during rotation of the drum.

The centrifugal throwing wheels may be mounted on a cantilevered tube which includes an elongated screw for distributing abrasive particles fed into the tube to the individual throwing wheels. The tube and its throwing wheels may be mounted for oscillatory movement and may be connected to a structural member which is suspended from an overhead monorail to facilitate the insertion of the tube into the drum and its removal Drain holes may be provided to permit abrasive particles or other treating media to drain into an oscillator conveyor which in turn may have a screen deck at the exit end of the drum to receive the treated parts.

THE DRAWINGS FIG. 1 is a side elevational view of a workpiece treating arrangement in accordance with this invention;

FIG. 2 is an end elevational view of the apparatus shown in FIG. 1;

FIGS. 3 and 4 are cross-sectional views taken through FIG. 1 along the lines 33 and 44, respectively;

FIGS. 5 and 6, respectively, are a side view and end view of another embodiment of the present invention; and

FIGS. 7 and 8, respectively, are a side view and an end view of another embodiment of the present invention.

DETAILED DESCRIPTION FIGS. 1-4 show the workpiece treating apparatus 10 in accordance with this invention. As indicated therein the apparatus 10 includes an infeed tube 12 incorporating the center feed tube 14 of the type disclosed in U.S. Pat. No. 3,585,758, the details of which are incorpo rated herein by reference thereto. Parts 11 are fed through the center feed tube 14 and move longitudinally during the rotation of feed tube 12 by means of spiral conveyor 16. As pointed out in detail in U.S. Pat. No. 3,585,758, this infeed tube arrangement includes the bridging element or center feed tube 14 connected to the first flight of spiral conveyor 16 so that the parts or workpieces that are fed therein will not be struck by the first flight of the spiral conveyor, thereby minimizing the possibility of breakage.

From the infeed tube 12 the parts are conveyed to the treating drum 18. Drum 1 8 and infeed tube 12 are of one-piece construction and differ from each other in that drum 18 includes a spiral conveyor 20 which is merely of sufficient width or projects into the drum only an amount sufficient to convey the workpieces therethr'ough whereas spiral conveyor 16 in the infeed tube 12 projects a substantial amount into the infeed tube as described in U.S. Pat. No. 3,585,758. A plurality of openings 22 are provided about the periphery of drum 18 to permit drainage of the abrasive particles and sand. Conversely, if the drum is of solid construction, the flight of spiral conveyor 20 would function to move the abrasive particles and sand to the exit end of drum 18.

In addition to the many. advantages obtained by utilizing the slatless drum 18 in place of the conventional slat conveyor or trough or prior art devices is the avoidance of the problem frequently attendant with prior art devices wherein with a slat conveyor some parts do not move across the conveyor to the exit end at a uniform speed and, at times, some parts even stay in the slat conveyor for hours. This problem is overcome with slatless drum 18 since, because of its cylindrical shape, the drum can include spiral conveyor 20 to insure a uniform and continuous movement of the parts through the drum.

A further advantage with the inventive arrangement is that with prior arrangements the infeed spiral'must push the parts or workpieces onto and across the slat conveyor. This creates additional thrust loads on the infeed tube section. With the inventive arrangement, however, the spiral 20 in the slatless drum, as noted above, uniformly moves all parts to the exit end of the machine. Since the infeed tube 12 and the blast drum 18 are of one-piece construction, no high thrust loads are present other than the normal thrust required to screw the parts to the exit end of the drum.

At the exit end of the blast drum 18, the parts are dumped onto the screen deck 24 of suitable oscillating conveyor 26. The abrasive particles fall through screen deck 24 and are recirculated in a conventional manner by elevator 28 through separating system 30 into feed hopper 32. A plurality of rubber curtains 34 act to prevent the abrasive particles from being deflected out of drum 18. The cleaned parts are carried by the oscillating conveyor 26 by any suitable means such as a further conveyor disposed at the discharge end of conveyor 26.

A feature which enables apparatus to function so effectively is the recent development of the type of centrifugal throwing wheels described in US. Pat. No. 3,521,406, the details of which are incorporated herein by reference thereto. In this respect, slat conveyors had been necessary because the trough-like arrangement created an opening through which the blast wheels could project the abrasive particles. With a solid drum such as drum 18, no such openings are present. The development of the throwing wheels described in US. Pat. No. 3,521,406 wherein each wheel is mounted directly on its motor shaft, however, permitted the wheels to be inserted into the drum fromv either the open exit end or from the entrance end if desired.

As shown in FIG. 3, each throwing wheel 36 includes a motor 38 with a runnerhead 40 mounted directly on the motor shaft 42 and a plurality of throwing vanes 44 radially mounted on runnerhead 40. Abrasive particles are supplied through spout 46 from support tube 48. The throwing wheel 36 is mounted for universal movement about a plurality of axes as described in US. Pat. No. 3,521,406.

As shown in FIG. 1, the individual throwing wheels 36 are mounted on a cantilevered tube 48 which in turn is secured to a structural member 50. Structural member 50 is suspended from a monorail system 52 which includes horizontal track 54, wheels 56 and vertical mounting member 58. In this manner, the entire unit comprising tube 48 and wheels 36 may be easily moved into blast drum 18 during operation and out of the drum for maintenance or other purposes. Structural memberSO is so designed in shape as to conform to the size and shape of an opening at the exit end of the cabinet 60 so that when the tube 48 is inserted inside drum 18, the opening in cabinet 60 is closed by structural member 50 to prevent abrasive particles from ricocheting out of the blast drum. During use, structural member 50 is rigidly secured to the cabinet by bolts or other suitable fastening means.

As shown in FIG. 3, mounted within hollow tube 48 is an elongated screw conveyor 62 or any other suitable conveying means to convey the abrasive particles fed into the tube to the spouts 46 of the individual throwing wheels 36. The space between the screw conveyor 62 and the inner surface of tube 48 is advantageously utilized to house electrical cables 64 to the motors 38 and also to carry hoses 66 for feeding cooling air to motors 38. Additionally, drive means 68 (FIG. 2) are provided to oscillate the entire unit of tube 48 and wheels 36 to give better blast coverage. This oscillation .means may take any suitable form and as shown in FIG. 4, may include a bearing surface 70 to which tube 48 is mounted, with arcuate slots 72 being in the bearing surface to control the amount of oscillation of tube 48.

As shown in FIGS. l-3, infeed tube 12 and drum section 18 may be rotated by any suitable means such as by gear drive 74 to tumble the workpieces 11 being fed therethrough. During this rotation, abrasive particles are supplied to the hollow interior of tube 48 from feed hopper 32 through an opening in cabinet 60 and through any suitable valve such as gate valve 76 into elongated feed spout 78. Because of the widened feed spout 78, the falling abrasive particles drop into the spout even during oscillating of tube 48. I

The workpiece treating arrangement 10 in accordance with this invention has a number of distinct advantages over the conventional prior art slat conveyor arrangements. For example, the inventive arrangement eliminates the slat conveyor with its complex system of chains, sprockets, drives, rollers, slats and costly maintenance problems. Additionally, with the inventive arrangement there is continuous and positive movement of all work through the barrel. Moreover, a much lower noise level is obtained by mounting the blast wheels inside the blast drum 18 which in turn is within housing 60. Additionally, better and more uniform cleaning may be obtained by oscillating the throwing wheels. Further, a complete unit is less expensive than an equivalent slat type continuous barrel.

FIGS. 5 and 6 illustrate another embodiment of the present invention wherein the infeed tube 12 which incorporates a center tube 14 is not utilized, but the drum 18 includes a plurality of throwing wheels 36 disposed therein for treating workpieces. The work is fed through a tube 82 which deposits the workpieces within the interior of the drum 18. The arrangement overcomes the problems associated with slatted conveyors as hereinbefore discussed.

An elongated member 84 extends lengthwise through the upper open portion of the drum 18. Elongated member 84 is substantially parallel to the axis of rotation of the drum 18 which is substantially horizontally disposed. The elongated member 84 is slidably supported at each end exterior to the drum 18 by rollers 86. Each of the rollers 86 is supported by an upright column 88.

As illustrated in FIG. 5, the elongated member 84 is a beam. It is contemplated that the elongated member 84 can be any suitable shape, including the hollow tube construction hereinbefore described. A conduit 90 is associated with the elongated member 84. If elongated member 84 is a beam, the conduit 90 is separate and supported thereby as illustrated in FIGS. 5 and 6. If elongated member 84 is a hollow tube 48 as illustrated in FIG. 1, the hollow interior portion of the tube 48 forms a conduit for the passage of treating particles.

One end of the conduit 90 exterior to the drum 18 is connected to a source 92 of abrasive treating particles. The conduit 90 is connected to feed spouts 46 for the flow of treating particles to the individual throwing wheels 36. An elongated screw conveyor 62 can come niently be used to move the treating particles along the conduit 90 to the feed spouts 46. FIGS. 5 and 6 illustrate an embodiment wherein the elongated member 84 can be oscillated to obtain a highly uniform cleanmg.

FIGS. 7 and 8 illustrate an embodiment of the present invention wherein the end of elongated member 100 engages in a socket 101, thereby providing support for both ends of the elongated member, during operation of the machine. The above-mentioned socket is disengaged when the assembly supporting wheels 36, is moved out of the drum for maintenance. During maintenance the elongated member is cantilevered from structural member 50.

Conduit 102 carries the treating particles to the individual throwing wheels 36.

The workpieces are fed into the drum 18 by means of conveyor 103 passing thru a plurality of rubber curtains 104.

In another embodiment of the present invention, the said conduit 102 is the elongated member and engages in the aforementioned socket 101.

The advantage of using the above-mentioned socket is the additional support obtained for the elongated member 100 or 102 enabling more throwing wheels 36 to be supported than would be practical without the socket.

With the exception of infeed tube 14 and special conveyor 16 all other features shown on FIG. 1 are incorporated in the embodiments shown in FIGS. 7 and 8.

What is claimed is:

1. A workpiece treating apparatus comprising a drum having a hollow interior and open ends for accomodating an axial flow of workpieces therethrough, means for rotating said drum about an horizontal axis, an elongated support member extending lengthwise through said drum in spaced relation above said horizontal axis and having opposite end portions protruding from respective open ends of said drum, separate means located exteriorly of said drum for supporting respective ones of said opposite end portions exteriorly of said drum, throwing wheel means mounted on said support member within said drum, and means for supplying workpiece treating particles to said throwing wheel means, said separate means including means for allowing axial movement of said support member and said throwing wheel means within said drum.

2. Apparatus as defined in claim 1 wherein said support means comprises an elongated beam, said separate means comprises a pair of upright columns spaced from each other and located adjacent opposite ends of said drum, and said means for allowing movement of said support member comprises roller means carried by said upright columns.

3. Apparatus as defined in claim 1 wherein said support means comprises an elongated member, said separate means comprises a socket located adjacent one end of said drum for releasably supporting one end of said elongated member and a moveable structural member secured to the other end of said elongated member adjacent the other end of said drum, and said means for allowing movement of said support member comprises a means located exteriorly of said drum and supportingly connected to said structural member. 

1. A workpiece treating apparatus comprising a drum having a hollow interior and open ends for accomodating an axial flow of workpieces therethrough, means for rotating said drum about an horizontal axis, an elongated support member extending lengthwise through said drum in spaced relation above said horizontal axis and having opposite end portions protruding from respective open ends of said drum, separate means located exteriorly of said drum for supporting respective ones of said opposite end portions exteriorly of said drum, throwing wheel means mounted on said support member within said drum, and means for supplying workpiece treating particles to said throwing wheel means, said separate means including means for allowing axial movement of said support member and said throwing wheel means within said drum.
 2. Apparatus as defined in claim 1 wherein said support means comprises an elongated beam, said separate means comprises a pair of upright columns spaced from each other and located adjacent opposite ends of said drum, and said means for allowing movement of said support member comprises roller means carried by said upright columns.
 3. Apparatus as defined in claim 1 wherein said support means comprises an elongated member, said separate means comprises a socket located adjacent one end of said drum for releasably supporting one end of said elongated member and a moveable structural member secured to the other end of said elongated member adjacent the other end of said drum, and said means for allowing movement of said support member comprises a means located exteriorly of said drum and supportingly connected to said structural member. 